LIBRARY OF CONGRESS. 



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UNITED STATES OF AMERICA. 




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MANUAL 



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Lunatellus Globe, 



N rAINING A COMPLETI COURSE 



Problems and Illustrations 



FVSD.l M EH TA L 1'RINCIPLES 



Geography and Astronomy, 



FOR THE USE OF 



Teachers, Schools § Families, 

■ ■ 

Rev, JOHN HRUIS, R, M., 

AUTHOR OF "ELEMENTS "I ASTRONOMY," 
ALLEGHENY CITY, PA. 



Entered according to Act of Congress, in the year 1884, by 

JOHN DAVIS, 
in the Office of the Librarian of Congress, at Washington. 



PRINTED BY 

PAUL HUETHER, ALLEGHENY. 
1884. 



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PREFACE. 



This Manual is a guide to the proper use of the Lu- 
natellus Globe, which faithfully illustrates the principles of 
Geography and Planetary motion. The pupil's greatest 
difficulty in obtaining a correct knowledge of Mathemat- 
ical Geography and Astronomy, often arises from previ- 
ous false conceptions of their principles acquired some- 
times with the use of imperfect Apparatus. This fact in- 
truding itself so frequently in the Class-room, suggested 
the necessity of the Lunatellus Globe; which on account 
of its convenience, accuracy and durability, is rapidly fil- 
ling a vacuum in Families and Schools. It contains three 
bodies, one of them being a twelve inch Terrestrial Globe, 
which by their relations and motions exhibit the natural 
relations and motions of the Sun, Earth and Moon. The 
body representing the Sun, is made to turn on its axis, 
while the Terrestrial Globe, having its axis properly in- 
clined, has a similar motion, and at the same time revolves 
in its orbit around the Sun, showing his rising and set- 
ting, his Declination, or apparent motion North and South, 
the change of Seasons, the vicissitudes of Day and Night 
and their alternate increase and decrease in length. The 
body representing the Moon, is made to revolve around 



PREFACE. 

the Earth in an elliptical orbit, whose plane is at an angle 
of about five degrees with the plane of the Ecliptic; also 
around the Sun and on her own axis, exhibiting her days 
and nights, changes, phases and fulling and the interesting- 
phenomena of Solar and Lunar Eclipses. The principles 
of Geography and Astronomy and t-he phenomena result- 
ing therefrom, being involved in the form and movements 
of this Apparatus, the manual contains a consecutive 
series of Problems and Examples based upon these prin- 
ciples \vhcreby the pupil may have an accurate, and prac- 
tical illustration of their meaning. 



The Author while preparing this Manual, carefully consult- 
ed the best English, French and American Authorities on the 
use of Globes, with the view of having it simple, brief and at 
the same time sufficiently comprehensive for the purpose for 
which it is designed. 



The Definitions and Explanations which relate to the sub- 
jects considered in this Manual are, for the sake of convenience 
placed after the Illustrations and Problems. And in connec- 
tion with each of the Illustrations and Problems reference is 
given to such Definitions and Explanations as should be studied 
with care before entering upon its solution. 



PART I. 

ILLUSTRATIONS. 

I. To illustrate the motions of the Sun, Earth and 
Moon. 

II. To illustrate the Plane of the Ecliptic and its re- 
lation to the Plane of the Equator. 

III. To illustrate the Inclination of the Earth's axis 

and its Parallelism. 

IV. To illustrate the cause of Day and Night. 

V, To illustrate the equality of Day and Night on the 
21st of March, or 21st of September. 

VI. To illustrate the cause of long Days and short 

Nights in the Northern Hemisphere. 

VII. To illustrate the cause of long Days and short 
Nights in the Southern Hemisphere. 

VIII. To illustrate the cause of six months Day at the 
North Pole and six months Night at the South 
Pole, and vice versa* 

IX. To illustrate the cause of the inequality in the 
length of Days and Nights. 

X. To illustrate the rising and setting of the Sun. 

XI. To illustrate the cause of Winter in the Northern 
Hemisphere and Summer in the Southern Hem- 
isphere. 

XII. To illustrate the cause of Summer in the Northern 
Hemisphere and oi Winter in the Southern 
Hemisphere. 



PART II. 

PROBLEMS. 

I, To find the Longitude of a given place. 

II. To find all places which have the same Longitude 
as that of any given place. 

III. To find the Latitude of a given place. 

IV. To find all places which have the same Latitude 

as that of any given place. 

V, The Longitude and the Latitude of any place 
being given to find the place. 

VI. Two places being given to find their difference of 
Latitude. 

VII, Two places being given to find their difference of 
Longitude. 

VIII. To find the distance between to places. 

IX. To find places equally distant from a given place. 

X. The Latitude of a place, its distance and general 
direction from a given place, bekig given, to 
find the place whose Latitude is given. 

XI. The Longitude of a place, its distance and gener- 
al direction from a given place, being given, to 
find the place whose Longitude is given. 

XII. Any parallel of Latitude being given, to find how 
many miles make a degree of Longitude on it. 



PART III. 



ILLUSTRATIONS. 



XIII. To illustrate the distribution of Solar light and 

heat when the Earth is at either Equinox, 

XIV. To illustrate the distribution of Solar light and 

heat on the longest day in the Northern Hem- 
isphere. 

XV. To illustrate the distribution of Solar light and 
heat on the longest day in the Southern Hem- 
isphere. 

XVI. To illustrate the succession of the Seasons. 

XVII. To illustrate the cause and width of the Zones. 

XVIII. To illustrate Sun time and Clock time alternately 
fast and slow, 

XIX. To illustrate the Sun rising North of the East 
point and seating XoYth of the West point 
during one-half of the year, and rising South 
of the East point and setting South of the 
West point during the other half of the year, 

XX. To illustrate the cause of the Sun rising earlier 
on places East of us, 

XXI. To illustrate the cause of the apparent motion 

of the Sun, Moon and Stars, from East to West. 

XXII. To illustrate the declination of the Sun, or his 

apparent motion North and South. 

XXIII. To illustrate the relation of the Sun's declination 

to the Horizon every day in the year. 

XXIV, To illustrate the relative position of the Earth 

to the Sun every day in the year. 



PART IY. 

PROBLEMS. 

XIII. To find at what rate per hour any given point 

on the Earth's Surface moves by its axial ro- 
tation. 

XIV. To find the difference of time between any two 

places which are not under the same Meridian. 
XV. The hour being given at anyplace, to determine 
what hour it is at any other given place. 

XVI. To find the Sun's place in the Ecliptic on any- 
given day in the year, 

XVII, To find the Sun's Longitude on any given day in 
the year. 

XVIII, To find the Sun's Declination and Right Ascen- 
sion for any given day in the year. 

XIX, To find on what two days of the year, the Sun 
will be vertical at any given place within the 
Tropics. 

XX, To find all places where the Sun is vertical on 
any given day. 

XXI. To find that part of the Globe where the Snn 
ceases to rise and that part where he ceases to 
set on any given day. 

XXII. To illustrate a Right Sphere. 

XXIII. To illustrate an Oblique Sphere. 

XXIV, To illustrate a Parallel Sphere. 



PART Y. 

ILLUSTRATIONS. 

XXV. To illustrate the Sun and Earth as always in 
opposite Signs of the Zodiac. 

XXVI. To illustrate the inequality of Sidereal and 

Solar days. 
XXVII. To illustrate the Spring and Neap tides. 

XXVIII. To illustrate the effects on the tides of Solar 
and Lunar declination. 

XXIX. To illustrate the cause of the trade winds. 

XXX. To illustrate the influence of the Sun in pro- 
ducing the Monsoons. 
XXXI. To illustrate the cause of land and sea breezes. 

XXXII. To illustrate the Moon as always having the 
same side towards the Earth. 

XXXIII. To illustrate the length of Lunar days and 

nights. 

XXXIV. To illustrate the Conjunction, Quadrature, 

Opposition and Phases of the Moon, 

XXXV. To illustrate the eccentricity of the Moon's 
orbit. 

XXXVI. To illustrate the relation of the Moon's orbit 
to the Plane of the Ecliptic. 

XXXVII. To illustrate the Sidereal and Sy nodical rev- 
olutions of the Moon. 

XXXVIII. To illustrate Solar and Lunar Eclipses. 



LUNATELLUS GLOBE. 

Letters representing the principal parts of the 
Lunatellus Globe. 

A, The Arm which carries the Earth and Moon. 
F, The Semi-circle, representing the plane of the Ecliptic. 
C, The Circle of Illumination. I, The Calendar Index. 
H, The Hour Index, B, The Base. 

Q, The Quadrant. S, The Sun. 

M, The Moon. E, The Earth. 

D, The Cap which carries the Sun. 

Directions for putting the parts together. 

ist. Place the rear end of the Arm A in the Cap D and 
tighten the screws in the Cap. Then revolve the gear in 
the Arm A with the fingers, till the central axis of the 
Globe over which we place its tubular axis, inclines di- 
rectly towards the center of the Cap D. 

2nd. Place the Cap Don the central part of the Base 
B, with the Arm A directly over the word Solstice, June 
21st, and fasten the Cap, Arm and Base together with the 
bolt which contains a thumb nut. 

3rd. Place the tubular axis of the Globe on its central 
axis which is carried by the Arm A, so that the gear on 
the upper end of the standard, fixed in the outer end of 
the Arm A and the gear connected with the South Pole 
of the Globe, will come together; observing at the same 
time to have the outer ends of the yoke extending from 
the South Pole equally distant from the center of the 
Cap D. 



LUNATELLUS GLOBE. 

4th. Place the Hour Index on the North end of the 
tubular axis of the Globe, and attach with a screw to the 
central axis of the Globe, the small metal bearing, con- 
taining a square hole in one end and a knob with a groove 
in it loosely pivoted in the other end ; observing to in- 
cline the bearing in putting it on directly away from the 
center of the Sun when it is in place, and then put the 
inner edge of the Circle of Illumination in this groove, 
as it is being connected to the Instrument by the pivots 
of the yoke. 

5th. Finally, place the Sun S with the Semi-circle F 
attached, at right angles with his Polar axis, on the cen- 
ter of the Cap D, and adjust the Moon Rod as the parts 
at the outer end of the Arm A suggest, and the Appara- 
tus will be ready to operate. 



The Lunatellus Globe is the only device in existence 
which faithfully illustrates the mutual relations and various 
movements of the Sun, Earth and Moon. It is composed 
wholly of Iron Brass and Steel, except the Terrestrial 
Globe which represents the Earth, and the Chart that cov- 
ers the Base. 

BASE AND CHART. 

The Base of the Instrument is cast in one piece and 
has p!a ed upon it a Chart showing how the Sun, Earth 
and Moon perform their functions, as members of the 
£olar System, every day and hour in the Year. 

T!ie Chart contains in their proper relations, the Signs 
of the Zodiac, the months and days of the Year, the va- 
rious lengths of the Seasons, the periods when the Sun is 
fast and slow, the degrees of Celestial Longitude, the 
Perihelion, Aphelion, Solstitial and Equinoctial points, 
together with other Symbols relating to the various move- 
ments of the Apparatus. 

SUN AND SEMI-CIRCLE. 

The Sun is represented by a body composed of Brass 
and connected by one of its Poles to the gearing within. 
To the Equator of this body is attached a Semi -circle 
which, when properly adjusted represents the Plane of 
the Ecliptic. 



LUNATELLUS GLOBE. 

EARTH. 

The Earth is represented by a Terrestrial Globe, twelve 
inches in diameter, and is pivoted by the South Pole to the 
gearing which gives it rotary motion. 

MOON. 

The Moon is represented by a Globe relative in size to 
that of the Terrestrial Globe, and is attached at one of its 
Poles to the outer end of a bent rod, the inner end of 
which is loosely pivoted to an upright placed on a disk 
which revolves, carrying the Moon around the Earth and 
and causing her to cross and recross the plane of the 
Ecliptic at an angle of about 5 degrees, as both Earth 
and Moon revolve around the Sun. 

CIRCLE OF ILLUMINATION. 

The Circle of Illumination is a flat Metallic Ring 
surrounding the Globe and loosely pivoted in the plane 
of the Equator, so that it is at liberty to change its posi- 
tion every moment as the Globe revolves around the Sun. 

Note. — This is the only Invention which produces this result In a 
natural way. 

CALENDAR INDEX. 

The Calendar Index is located in the Arm A that car- 
ries the Earth and Moon around the Sun, and it can be 
set in a moment by revolving the Arm, so as to point to 
any day of any month, or any day of the Year. 



LUNATELLUS GLOBE. 

.QUADRANT OF ALTITUDE. 
The Quadrant of Altitude is a flexible strip of Metal 
graduated into equal parts, each corresponding in length 
to a degree on the Terrestrial Globe and bent when in 
use so as to closely fit its surface. 

GEARING. 

This Apparatus is operated by Brass and Steel Gear- 
wheels, some of which are inside of the case and some en- 
closed in the outer end of the Arm that carries the Earth 
and Moon around the Sun. 

UTILITY AND ECONOMY. 

The principles of Geography and the various positions, 
-motions and phenomena of the Sun, Earth and Moon are 
expressed by this Instrument with such precision and accu- 
racy that more can be learned with its use in a few lessons, 
than can be learned m months without it, hence its ne- 
cessity in every School and Family. 

The Lunatellus Globe is manufactured by skillful 
Mechanics in the most sustantial manner , and an exact du- 
plicate of any part of it may be obtained at any time, by 
applying to the Patentee. 



EQUINOXES AND SOLSTICES. 

That the Language of this Manual may be adapted 
with equal advantage to instruction in Schools and Fami- 
lies both North and South of the Equator; and that there 
may be no misapprehension, as is frequently the case in 
the use of terms, descriptive phrases are employed when 
necessary, which convey definite ideas. Instead of refer- 
ring to the four Cardinal points of the Earth's orbit in the 
illustrations within, by their usual names Vernal Equinox, 
Autumnal Equinox, Summer Solstice and Winter Solstice, 
they are designated by the first points of the Signs where 
they are, and simply named Equinox and Solstice as the 
case may be. The Sun and Earth are at opposite Solstice^ 
at the same time and also at opposite Equinoxes at the same 
time, consequently they are just entering opposite 
Signs. On the 21st of March the Sun is at the first point 
of the Sign Aries which is named Vernal Equinox and from 
which Celestial Longitude and Rirht Ascension are reck- 
oned. On the same date, 21st of March, the Earth 
(though at the first point of the Sign Libra) is sometimes 
said to be at the Vernal Equinox, as Spring in the 
Northern Hemisphere immediately follows. Language 
equally ambiguous is frequently employed in expressing 
the relation of the Sun and Earth to the Solstices at 
different Seasons of the year. Hence to avoid all uncer- 
tainty as to the points referred to in the following illus- 
trations, they are definitely described by naming the first 
points of the Signs where they are. 



PART I 

ILLUSTRATION I. 

To Illustrate the Motions of the Sun, Earth and 
Moon. 

See Definition 50. 

It will be apparent if motion is imparted to the Arm 

A in the order of the Signs of the Zodiac, that the Sun's 

motion on his axis, the Earth's annual motion around the 

Sun and her daily motion on her axis, and the motions of 

the Moon around the Sun, around the Earth and also on 

her axis are in the same general direction, Eastward. 

Note. — The order of the Signs is as follows : Aries, Taurus, Gem- 
mini, Cancer, (Sic. 

ILLUSTRATION II. 

To Illustrate the Plane of the Ecliptic and its rela- 
tion to the Plane of the Equator. 

See Definitions 1 1, 17, 22, 23. 

As the Planes of the Equator and Ecliptic cross each 
other in the centre of the Earth at an angle of about 23^ 
degrees, by placing the Semi-circle F, which is attached 
to the Equator of the Sun in a horizontal position, it will 
show the natural relation of the Plane of the Ecliptic to 
the Plane of the Equator as the Earth revolves around the 
Sun. 



ILLUSTRATIONS. 

ILLUSTRATION III. 

To Illustrate the Inclination of the Earth's Aoois 
and its Parallelism. 

See Definitions 4, 24. 

As the axis of the Earth is inclined about 23*^ degrees 
to the Plane of the Ecliptic, by revolving the Earth 
around the Sun it will be apparent that its natural incli- 
nation is constantly maintained and also its parallelism. 

ILLUSTRATION IV. 

To Illustrate the Cause of Day and Night. 

See Definition 4. 

The Earth being globular and opaque, the Sun enlightens 
constantly that half next himself, making day, while the 
other half which is opposite to him is in darkness, making 
night. By giving the Arm A motion, the Earth will turn 
on its axis and that half next to the Sun will be turned 
into the shade of the Earth which is night, while the 
other half which is in darkness, will be turned into the 
light of the Sun which is day. 

Note. — That half of the Earth's surface on the opposite side of the 
Circle of Illumination C from the Sun is regarded as being in dark- 
ness. 

The Circle of Illumination is the metal ring which surrounds the 
Globe and it represents the line around the Earth which divides day 
from night. 



ILLUSTRATIONS. 

ILLUSTRATION V. 

To Illustrate the Equality of Day and Night on 
the 21st of March or 21st of September. 

See Definitions 5, 25, 30, 73, 74. 

Move the Arm A till it is over the First point of the 
Sign Aries, marked Equinox on the Base of the Instrument, 
or over the First point of the Sign Libra, also marked 
Equinox, and it will be apparent from the position of the 
Circle of Illumination that each Pole is equally distant 
from the Sun and that the light of the Sun extents to each 
Pole) consequently half of the Equator and half of each 
of the Parallels are in the presence of the Sun and half of 
each is in darkness. 

Now since the Earth turns with uniform motion on her 
axis each half \\\\\ revolve through the same space in the 
same period, hence day and night are equal. 

ILLUSTRATION VI. 

To Illustrate the Cause of Long Days and Sho t 
Nights in the Northern Hemisphere. 

See Definitions 75, 76. 

Bring the Arm A to the First point of the Sign Capri- 
cornus (marked Solstice), and the Circle of Illumination 
will be 23^ degrees distant from each Pole dividing the 
Northern Hemisphere, which is inclined towards the Sun 
into two unequal parts, with the larger part next the Sun: 
hence, as the Earth turns uniformly on her axis, the cause 



ILLUSTRATIONS, 

of Long days and Short nights in the Northern Hemis- 
phere will be apparent. 

ILLUSTRATION VII. 

To Illustrate the Cause of Long Days and Short 
Nights in the Southern Hemisphere. 

See Definition 77. 

Bring the Arm A to the First point of the Sign Cancer 
(marked Solstice), and the Circle of Illumination will be 
23*^ degrees distant from each Pole dividing the Southern 
Hemisphere which is inclined towards the Sun into two 
unequal parts with the larger part next the Sun; hence as 
the Earth turns uniformly on her axis, the cause of long 
days, and short nights in the Southern Hemisphere will 
be apparent. 

ILLUSTRATION VIII. 

To Illustrate the cause of Six Months Dai/ at the 

North Pole and Six Months Night at the 

South Pole, and vice versa. 

See Definitions 5, 15. 

Bring the Arm A to the First point of the Sign Libra 
(marked Equinox), and the Circle of Illumination C will 
be over the Poles. Move the Arm A in the order of the 
Signs, observing that the North Pole is irside towards the 
Sun, and the South Pole is outside of the Circle of Illumin- 
ation away from the Sun, till the Arm A reaches the first 
point of the Sign Aries (marked Equinox) when the Cir 



ILLUSTRATIONS. 

cle of Illumination C will be again over the Poles. 
Continue the motion of the Arm A, observing that the 
North Pole passes outside and the South Pole passes in- 
side the Circle of Illumination and remain so till the Arm A 
reaches the Equinox from which it started ; hence as the 
distance which the Earth has traveled around the Sun 
represents one year, each pole was in alternate light and 
darkness for half of this period. 

ILLUSTRATION IX. 

To Illustrate the Cause of the Inequality in the 
Length of Days and Nights. 

Were the Earth's axis perpendicular to the plane of the 
Ecliptic the Planes of the Equator and the Ecliptic would 
coincide, and day and night would be always equal, as the 
light of the Sun would constantly extend to each Pole ; 
but the inclination and constant parallelism of the Earth's 
Axis, and her annual motion, as may be observed by giving 
the Globe a complete revolution around the Sun from 
either Equinox will show each Hemisphere to be unequally 
divided during each half year by the Circle of Illumina- 
tion ; hence the inequality of the days and nights in each 
Hemisphere. 

ILLUSTRALION X. 

Ho Illustrate the Rising and Setting of the Sun. 

Move the Arm A in the order of the Signs and the Globe 
will turn Eastward on its axis, thereby causing those por- 
tions of the Globe that are in the darkness or away from 



ILLUSTRATIONS. 

the Sun to pass under the Circle of Illumination into the 
presence or light of the Sun, and those portions of the 
Earth that are in the light of the Sun to pass under the 
Circle of Illumination away from the Sun into darkness. 

ILLUSTRATION XI. 

To Illustrate the Cause of Winter in the Northern 

Hemisphere and Summer in the Southern 

Hemisphere. 

See diagram of Summer and Winter Rays on the Base B. 

Bring the Arm A to the first point of the Sign Cancer 
(marked Solstice) and the North Pole will be inclined 
away from the Sun; hence his rays will be oblique and the 
days short in the Northern hemisphere, and in the South- 
ern Hemisphere the Sun's rays will be more direct and the 
days long, making Winter in the former and Summer in 
the latter. 

ILLUSTRATION XII. 

To Illustrate Summer in the Northern Hemisphere 
and Winter in the Southern Hemisphere. 

Bring the Arm A to the first point of the Sign Capricor- 
nus (marked Solstice) and the North Pole will be inclined 
towards the Sun; hence his rays will be more direct North 
of the Equator and the days long in the Northern Hemi- 
sphere, and in the Southern Hemisphere the Sun's rays 
will be oblique and the days short, making Summer in the 
former and Winter in the latter. 



PART II. 

PROBLEM I. 

To Find the Longitude of a given Place. 

See Definitions 48, 26, and Notes. 
Count the number of degrees on the Equator of the 
Globe, East if the given place is East, or West if the 
given place is West, between the Prime Meridian and the 
Meridian passing through the given place and it will be 
the required Longitude. 

EXAMPLES. 

1. What is the Longitude of Ottawa? 

2, What is the Longitude of Tokio? 

PROBLEM II. 

To Find all Places which have the same Longitude 
as that of a given Place. 

Find the Longitude of the given place by Problem I. 
and under the Meridian passing through the given place 
will all other places be found which have the same Longi- 
tude. 

EXAMPLES. 

1. What is the Longitude of Montevideo? 

2. Find other places having the same Longitude. 

3. What is the Longitude of Quebec? 

4. Find other places having the same Longitude. 



PROBLEMS AND EXAMPLES. 

PROBLEM III. 
To Find the Latitude of a given Flaoe* 

See Definitions 18, 46. 
Find the given place on the Globe and lay the Quad- 
rant on the Globe with O on the Equator and its gradu- 
uated edge touching the place and at right angles wi h 
the Equator, and the number of degrees counted on the 
Quadrant from the Equator to the given place will be the 
Latitude required. 

Note. — For the sake of brevity the word Quadrant is used instead of 
the phrase "Quadrant of Altitude. ,, 

Note. — The Quadrant of Altitude is ^.flexible strip of metal gradu- 
ated into equal parts, each corresponding in length to a degree on the 
Globe and bent when in use so as to lit its surface. 

EXAMPLES. 

i. What is the Latitude of St. Paul? 
2. What is the Latitude of Santiago? 

PROBLEM IV. 

'•To Find all places ivhicJi have the same Latitude 
as that of a given Place* 

See Definition 30. 
Find the Latitude of the given place by Problem III. 
and imagine a Parallel drawn through the given place, 
and all other places on this Parallel will have the same 
Latitude as that of a given place. 

EXAMPLES, 

i. What is the Latitude of Paramarabo? 



PROBLEMS AND EXAMPLES. 

2. Find other places having the same Latitude, 

3. What is the Latitude of Bahia? 

4. Find other places having the same Latitude. 

PROBLEM V. 

The Longitude and Latitude of any Place being 

given to find the Place. 

See Definitions 46, 48. 

Find the given degree of Longitude as in the first part 
of Problem I. and place the Quadrant on the Globe at 
right angles to the Equator, with O at the given degree 
of Longitude, and the required place will be found under 
the degree on the Quadrant corresponding to the given 
Latitude. 

EXAMPLES. 

i. Find the Point on the Globe whose Longitude is 150 
degrees East and Latitude 40 degrees South. 

2. Find the Point on the Globe whose Longitude is 10 
degrees West and Latitude 15 degrees North. 

PROBLEM VI. 

Two Places being given to find their difference 
of Latitude. 

Find the Latitude of each place by Problem III. and 
if both places are on the same side of the Equator, sub- 
tract the less number of decrees of Latitude from the 
greater and the remainder will be the difference of Lati- 
tude; but if the Latitude of one of the places is North of 



PROBLEMS AND EXAMPLES. 

the Equator and that of the other South of the Equator, 

add them together and their sum will be their difference of 
Latitude. 

EXAMPLES. 

i. What is the difference of Latitude between Pitts- 
burgh and Charleston? 

2. What is the difference of Latitude between Cape 
Town and Cairo? 

PROBLEM VII. 

Two Places being given to find their Difference of 
Longitude. 

See Definition 21, Note 3d, and Definition 26, Note 1st. 

Find the Longitude of each place by Problem I. and if 
both places are East or both places West of the Prime 
Meridian, subtract the less number of degrees from the 
greater for the difference of Longitude; but if one place 
is East and the other West of the Prime Meridian, add 
them together and their sum if it be less than 180 degrees 
will be the difference of Longitude. 

If the sum exceeds 180 degrees subtract it from 360 
degrees for the difference of Longitude. 

EXAMPLES. 

1. What is the difference of Longitude between Copeu- 
hagen and Pekin? 

2. What is the difference of Longitude between Madrid 
and Vienna? 



PROBLEMS AND EXAMPLES. 

PROBLEM VIII. 

To find the Distance between two Place** 

Place O of the Quadrant over one of the places on the 

Globe and extend it to the other, and the number of 

degrees between the two places will be the distance in 

degrees which multiplied by 60 will give the distance in 

Geographical miles, or multiplied by 69.1 will give the 

distance in Statute miles. 

xfoTE. — Sixty Geographical make a degree and 69.1 Statute miles 
make a degree. 

EXAMPLES. 

i. What is the distance in Geographical miles between 
New York and San Francisco? 

2. What is the distance in Statute miles between 
Philadelphia and Mobile? 

PROBLEM IX. 

To Find Places Equally Distant from a given 
place, 

„ lace O of the Quadrant on the given place as a centre 
of motion and move the Quadrant around this centre on 
the surface of the Globe, and all plaees over which the 
same degree of the Quadrant passes are equally distant 
from the given place. 

EXAMPLES. 

1. Find two places equally distant from Boston. 

2, Find four places equally distant from Denver. 



PROBLEMS AND EXAMPLES. 

PROBLEM X. 

The Latitude of a place, its distance and general 

direction from a given place being given, to find 

the place whose Latitude is given. 

If the distance is given in miles, convert the miles into 
degrees; then place O of the Quadrant over the place 
and move the other end of it Eastward if the required 
place is Eastward, or Westward if the required place is 
Westward, till the degree marked on it representing the 
distance arrives at the Parallel of Latitude indicating the 
Latitude of the required place and this point will show 
the place required. 

EXAMPLES. 

i. Find the place whose Latitude is 40 degrees North 
and distant from Vera Cruz in a North-western direction 
1,680 Geographical miles. 

2. Find the place whose Latitude is 20 South and 
distant from Pernambuco in a South-western direction 
2,145 Statute miles. 

PROBLEM XI. 

The Longitude of a place, its distance and general 

direction from a given place being given, to find 

the place whose Longitude is given* 

Reduce the distance if given in miles to degrees; then 
place O of the Quadrant over the given place and move 
the other end of it Northward if the required place is 



PTOBLEMS AND EXAMPLES. 

Northward, or Southward if the required place is South- 
ward till the degrees marked on it representing the 
distance arrives at the given Meridian which point is the 
place required. 

EXAMPLES. 

i. Find the place whose Longitude is 90 degrees West 
and distant from Louisville in a South-western direction 
540 Geographical miles. 

2. Find the place whose Longitude is 113 degrees East 
and distant from Teheran in a South-eastern direction 
3,550 Statute miles. 

PROBLEM XII. 

Any Pa allel of Latitude being giv n to find how 
many miles make a, degree of Longitude on it* 

Place the Quadrant on the given Parallel and note th e 
number of degrees on it between two Meridians 15 degrees 
apart; then multiply this number by 4 if Geographical 
miles are required, or by 4.6 if Statute miles are required. 

Note. — It will he seen that if the distance between two Meridians 
15 decrees apart be measured on the Equator, it will also measure 15 
degrees on the Quadrant, and this number multiplied by 4 wil give 60 
the number of Geographical miles in a degree, or if multiplied by 4.6 
it will give 69, nearly the number of Statute miles in a degree. As 
we go toward the Poles, the degrees of Longitude become smaller, 
and wile these same Meridians will still be distant from each other 15 
degrees of Longilude, the distance measured on the Quadrant, which 
is a uniform standard, Mill be less than 15 and this smaller number 
multiplied by the same multiplier 4 or 4.6, will give a smaller result, 



PROBLEMS AND FXAMPLES. 

i. e. fewer miles to a degree of Longitude, which is as it should be since 
the number of miles in a degree of Longitude decreases in exactly the 
same ratio as the number of degrees measured on the Quadrant. 

EXAMPLES. 

i. How many Geographical miles make a degree 
measured on a parallel 40 degrees from the Equator? 

2. How many Statute miles make a degree measured 
on a Parallel 65 degrees from the Equator ? 



PART III. 

ILLUSTRATION XIII. 

Te Illustrate the Distribution of Solar light and 
heat ivhen the Earth is at either Equinow. 

See Definition 5. 
Bring the Arm A to either of the Equinoxes, 21st of 
March or 21st of September, as marked on the Base B, 
and observe that the Circle of Illumination stands over 
the Poles of the Globe and that at the Equator the rays 
of the Sun are direct and oblique toward the Poles; hence 
the Solar rays are more intense at the Equator and the 
temperature gradually diminishes in the direction of 
each Pole. 

ILLUSTRATION XIV. 

To Illustrate the Distribution of Solar 

light and Heat on the longest day in 

the Northern Hemisphere. 

See Definition 31. 
Bring the Arm A to the First Point of the Sign 
Capricornus (marked Solstice), 21st of June, and observe 
that the Circle of Illumination is 23^ degrees distant 
from each Pole and that the North Pole is inclined towards 
the Sun causing the Sun's direct rays to fall on the 
Northern Tropic; hence the Solar rays are most intense 
on the Northern Tropic and the temperature gradually 
diminishes as we recede from this Tropic. 



ILLUSTRATIONS. 

ILLUSTRATION XV. 

To Illustrate the Distribution of Solar light 

and heat on the longest day in the 

Southern Hemisphere. 

See Definition 32. 
Bring the Arm A to the First Point of the Sign Cancer 
(marked Solstice), 22d of December, and observe that the 
Circle of Illumination is 23^ degrees distant from each 
Pole and that the South Pole is inclined towards the Sun 
causing the Sun's direct rays to fall on the Southern 
Tropic; hence the Solar rays are most intense on the 
Southern Tropic and the temperature gradually diminishes 
as we recede from this Tropic. 

ILLUSTRATION XVI. 

To Illustrate the Succession of the Seasons* 

As a rule the more direct the Sun's rays are on any 
portion of the Earth's surface the warmer it is. 

Bring the Arm A to the First Point of the Sign Libra 
(marked Equinox), when the Sun's rays will be direct on 
the Equator; hence Fall in the South Temperate Zone 
and Spring in the North Temperate Zone. 

Move the Arm A to the First Point of the Sign 
Capricornus (marked Solstice), when the Sun's rays will 
be direct on the Northern Tropic; hence Winter in the 
Southern Hemisphere and Summer in the Northern. 
Advance the Arm A to the First Point of the Sign Aries 



ILLUSTRATIONS. 

(marked Equinox), when the Sun's rays will be direct on 
the Equator; hence Spring in the South Temperate Zone 
and Fall in the North Temperate Zone. Continue to 
move the Arm A till it arrives at the First Point of t*he 
Sign Cancer (marked Solstice), when the Sun's rays will 
be direct on the Southern Tropic; hence Summer in the 
Southern Hemisphere and Winter in the Northern. 

ILLUSTRATION XVII. 

To Illustrate the Causes which determine 
the width of the Zones. 

See Definitions 35, 36, 37, $S. 39. 

Bring the Arm A to the First Point of the Sign 
Capricornus (marked Solstice), and it will be apparent by 
moving it in the order of the Signs till it arrives at the 
other Solstice, that the Sun's rays were direct on every 
parallel between the Tropics; hence the Tropics are the 
limits of the Torrid Zone and are located where they are 
by reason of the axis of the Earth being inclined 23^ 
degrees to the plane of the Ecliptic, its constant parallelism 
and the annual revolution of the Earth around the Sun, 
Thus the width of the Torrid Zone is 47 degrees which is 
double the inclination of the Earth's axis and the distance 
of the Polar Circles from the Poles is 23^ degrees which 
equals the inclination of the Earth's axis, and the 
Temperate Zones are bounded by the Tropics and Polar 
Circles, 



ILLUSTRATIONS. 

ILLUSTRATION XVIII. 

To Illustrate Sun Time and Clock Time 
alternately fast and slow. 

Move the Arm A till it is over the 15th of April, as 
marked in the Circle of Months on the Base B, and the 
Earth will be in the Sign Libra and the Sun will be in the 
Sign Aries, the opposite Sign. Revolve the Arm A once 
around the Sun in the order of the Signs and it may be 
readily seen by observing the Circle of Degrees on the 
Chart covering the Base B, that Sun time and Clock time 
are alternately Fast and Slow, and that they agree on the 
15th of April, the 15 th of June, the 1st of September, 
and the 24th of December. 

ILLUSTRATION XIX. 

To Illustrate the Sun's Rising North of the East 

Point and Setting North of the West Point 

during one half of the year, and his rising 

South of the East point and setting South 

of the West point during the other 

half of the year. 

Bring the Arm A to the First Point of the Sign Libra 
(marked Equinox), and it will be apparent that while the 
Earth is moving in the order of the Signs to the other 
Equinox, that the Sun will be North of the Equator ; 
hence he will rise North of the East Point and set North 
of the West Point during half of the year, and by contin- 
uing the Earth's movement around the Sun till she returns 



ILLUSTRATIONS. 

to the Equinox where she started, it is also apparent that 
the Sun will be South of the Equator during an equal 
period; hence he will rise South of the East Point and 
set South of the West Point during the other half of the 
year. 

NoTF. — The East and West Points are equally distant from the Poles 
of the Earth, and are ©n the Horizon where the Sun rises and s< b 
when the Days and Nights are equal. 

ILLUSTRATION XX. 

To Illustrate the cause of the Sun's rising earlier 
on places East of us. 

East is a relative term and in general means tne direc- 
tion of the rising Sun which rising results from the rotation 
of the Earth on its axis Eastward. To verify this fact 
with the Apparatus, bring the Arm A to the First Point of 
the Sign Aries (marked Equinox), and the Circle of 
Illumination will be over the Poles and will divide the 
Equator into two equal parts. Move the Arm A in the 
order of the Signs around the Sun and the Earth will 
rotate Eastward on her axis bringing into the presence 
of the Sun those portions of ttie Earth near the Eastern 
edge of the Circle of Illumination before those parts 
which are further West. 

ILLUSTRATION XXL 

To Illustrate the cause of the apparent motion of 
the Sun, Moon and Stars from East to West. 

Bring the Arm A to the First Point of the Sign Aries 
(marked Equinox), and if it is moved in the order of the 



ILLUSTRATIONS. 

Signs, the Earth will also revolve Eastward on her axis 
thereby producing the apparent Westward motion of the 
Sun and Moon, and of the Stars also were they properly 
related to the Apparatus. 

ILLUSTRATION XXII. 

To Illustrate the Declination of the Sun or his 
apparent motion North and South. 

See Definition 49, Note 1st. 

Bring the Arm A tfo the First Point of the Sign Cancer 
(marked Solstice) and the Sun's rays will be direct on 
the Southern Tropic. Move the Arm A in the order of 
the Signs and the Sun's rays will be direct successively on 
every Parallel till it arrives at the other Solstice when his 
rays will be direct on the Northern Tropic. Continue 
the motion of the Arm A and the Sun's rays will be direct 
successively on every Parallel till they are again direct on 
the Southern Tropic, thereby showing the Declination 
of the Sun North and South, which is caused by the 
inclination, of iheEastKs axis, its constant parallelism and 
her annual motion around the Sun. 

ILLUSTRATION XXIII. 

3P# Illustrate the relation of the Sun's Declination 

to the Circle of Illumination every day in 

the year. 

Bring the Arm A to the First Point of the Sign Aries, 
or Libra (marked Equinox), and the Circle of Illumina- 



ILLUSTRATIONS. 

tion will be over the Poles. Revolve the Earth around 
the Sun and the Circle of Illumination will recede from 
the Poles or approach them as the Sun recedes from the 
Equator or approaches it. 

ILLUSTRATION XXIV. 

To If lust rate the relative position of the Earth to 
the Sun every day of the year. 

Bring the Arm A to the First Point of the Sign Aries 
(marked Equinox), and then move it in the order of the 
Signs till the Arm A makes one entire revolution around 
the Sun, and the Globe, as the Arm A is passing over each 
day of each month as marked in the Circle of Months on 
the Base B, will sustain the same relative position to the 
Sun in the Apparatus that the Earth does to the natural 
Sun each day of the year. 



PART IV. 

PROBLEM XIII. 

To find at ivhat rate per hour any given point on 

the Earth's surface moves, by its 

axial rotation* 

If the given pomt is situated on the Equator, reduce i§ 
degrees to miles for the rate per hour; but if it is located 
between the Equator and either Pole, then find by Prob- 
lem XII. the number of miles that make a degree of 
Longitude in the Latitude of a given point, which number 
multiplied by 15 will give the rate per hour. 

EXAMPLES. 

1. At what rate per hour do the inhabitants of Berlin 
move by the rotation of the Earth on its axis? 

2. At what rate per hour do the inhabitants of Borneo 
move by the rotation of the Earth on its axis? 

PROBLEM XIV. 

To find the difference of time betiveen any two places 
which are not tinder the same Meridian. 

Find the difference of Longitude between the two 
places by Problem VII. and divide this difference in 
degrees by 15 and the result will be the difference of time^ 
required. 



PROBLEMS AND EXAMPLES. 
EXAMPLES. 

i. Find the difference of time between Norfolk and 
Salt Lake City. 

2. Find the difference of time between Belfast and 
Canton. 

PROBLEM XV. 

The Hour being given at any place, to determine 
what hour it is at any other given place* 

Find the difference of time between the two places by 
Problem XIV. then if the place whose time is required 
is East of that place whose time is given, add the diffe- 
rence to the given time; but if the place whose time is 
required is West, subtract this difference from the given 
time and the result will be the time required. 

EXAMPLES. 

i. If it is 8 o'clock A. M. at Liverpool, what time is it 
at Hamburg? 

2. If it is ir o'clock at Naples, what time is it at 

M^cca? 

PROBLEM XVI. 

To find the Sun's place on the Ecliptic on any 
given day in the Year. 

Find the given day in the Circle of Months on the Base 
of the Apparatus, and bring the Arm A over this day and 
directly under the opposite end of the Arm, will be found 



PROBLEMS AND EXAMPLES 

the Sign and the degree of the Sun's place in the Eelip- 
tic. 

Note. — The Zodiac contains 12 Signs and each Sign is supposed to 
be divided into 30 degrees, and each degree into 60 minutes, and each 
minute into 60 seconds. 

EXAMPLES , 

i. Find the Sun's place in the Ecliptic on the 22nd of 

July. 

2. Find the Sun's place in the Ecliptic on the 19th of 

February. 

PROBLEM XVII. 

To find the Sun's Longitude on any given 
day in the Year. 

See Definitions 62, 70. 
Find the Sun's place in the Ecliptic for the given day 
by Problem XVI. and directly opposite this point in the 
Circle of Longitude on the Base of the Apparatus, will be 
found the degree representing the Longitude of the Sun 
on the given day. 

EXAMPLES. 

1. Find the Sun's Longitude on the 20th of April. 

2. Find the Sun's Longitude on the 20th of October, 

PROBLEM XVIII. 

To find the Sun's Declination and Right Ascension 
for any given day in the Year. 

See Definition 49. 
Find the Sun's Longitude for the given day by Prob- 



PTOBLEMS AND EXAMPLES. 

lem XVII. and then count the same number of degrees 
of Longitude on the Ecliptic on the Globe in the order 
of the Signs from the First point of the Sign Aries to the 
Sun's place, and with the use of the Quadrant find the 
number of degrees between the Sun's place and the Equa- 
tor and it will express the required Declination. 

The Sun's Right Ascension is found by counting on the 
Equator the number of degrees, from the First point of 
the Sjgn Aries to the Meridian that passes through the 
Sun's place on the Ecliptic. 

Note. — The number of degrees expressing the Sun's Declination 
subtracted from 90 degrees gives his Polar Distance. 

EXAMPLES. 

i. Find the Sun's Declination and Right Ascension on 
the 22nd of August. 

2. Find the Sun's Declination and Right Ascension on 
the 20th of January. 

PROBLEM XIX. 

To find on ivhat two days of the Year the Sun will 

be vertical at any given place within 

the Tropics. 

wSee Definition 15. 
Find the Latitude of the given place with the Quadrant 
and find with the Quadrant also, two points on the Eclip- 
tic, on the same side of the Equator that have the same 
Latitude and note the Signs and degrees on the Ecliptic 



PROBLEMS AND FXAMPLES. 

where these points are ; then find the Signs and degrees 
corresponding to them on the Base of the Apparatus and 
bring the short end of the Arm A, successively over these 
points and directly under the Arm A, in the Circle of 
Months on the Base, will be found the months and days 
required. 

EXAMPLES. 

i. On which two days in the Year will the Sun be ver- 
tical at Bombay ? 

2. On which two days in the Year will the Sun be ver- 
tical at Lima ? 

PROBLEM XX. 

To find all places where the Sun is vertical 
on any given day. 

Find the Sun's Declination for the given day according 
to Problem XVIII, and to all places on the same side of 
the Equator and equally distant from it, will the Sun be 
vertical on that day. 

EXAMPLES. 

i. Find the Parallel on which the Sun is vertical on the 
21st of May. 

2. Find the Parallel on which the Sun is vertical on the 
2TSt of December. 



PROBLEMS AND EXAMPLES. 

PROBLEM XXI. 

To find tit at part of the Earth where the Stm ceases 

to rise and that pari where lie ceases to set 

on any given day. 

Move the Arm A that carries the Globe till its center 
is over the given day, as marked in the Circle of Months 
on the Base of the Apparatus, and observe the position of 
the Circle of Illumination near the Poles, and it will show 
on the Globe where the Sun has ceased to rise and also 
where he has ceased to set. 

EXAMPLES. 

i. Find those parts of the Earth where the Sun ceases 
to rise and set on the 21st of June. 

2. Find those parts of the Earth where the Sun ceases 
to rise and set on the 20th of October. 

PROBEM XXII. 
To Illustrate a Might Sphere. 

See Definitions 1, 2, 3, 51. 

Move the Arm A till its center is over the word Equinox 

as marked on the Base of the Apparatus, and the plane of 

the Circle of Illumination which may be considered as 

the Horizon, will coincide with the axis of the Globe ; 

hence the Equator, Parallels and Circles of Daily Motion 

are perpendicular to the Horizon. 

Note. — Circles of Daily Motion are Circles which the heavenly 
bodies seem to describe in consequence of the rotation of the Earth on 
its axis. 



PROBLEMS AND EXAMPLES. 
EXAMPLES. 

i. Where must we be located on the Earth that it may 
be to us a Right Sphere ? 

2. What would be the length of the Days and Nights 
on the Equator? 

PROBLEM XXIII. 

To Illustrate an Oblique Sphere. 

See Definitions 40, 41, 42, 53. 
Move the Arm A till its center is over the word Solstice 
marked on the Base of the Apparatus, and regard the 
Circle of Illumination as representing the Horizon^ 
and it will be apparent that the Equator, Parallels and 
Circles of Daily Motion are oblique to the Horizon. 

EXAMPLES. 

1. Where must we be located on the Earth that it may 
be to us an Oblique Sphere ? 

2. If the Earth's Axis were inclined 45 degrees to the 

plane of her orbit, what would be the width of the Torrid 

Zone, 

PROBLEM XXIV. 

To Illustrate a Parallel Spliere. 

See Definition 52. 
Detach the Circle of Illumination from the Globe and 
pinion it again in the Equator and turn it till its plane 
coincides with the plane of the Equator, and it will reper- 



PROBLEMS AND EXAMPLES, 

sent the Horizon of a Parallel Sphere ; hence the Equator, 
Parallels and Circles of. Daily Motion will be Parallel to 
the Horizon. 

EXAMPLES. 

i. Where must we be located on the Earth that it may 
be to us a Parallel Sphere? 

2. If we lived at the North Pole, in what part of the 
heavens wou'd the Pole Star appear? 



PART Y. 

ILLUSTRATION XXV, 

To show how the Sun and Earth are always in 
opposite Signs of the Zodiac. 

See Definition 80. 

The Zodiac being that part of the Celestial Sphere 
which lies about 8 degrees on each side of the plane of 
the Ecliptic, is divided into 12 equal parts called Signs, 
swid these Signs have associated with them 1 2 Constella- 
tions. (See Chart on the Base of the Apparatus.) As 
the Earth enters one Sign, the Sun enters the Sign oppo- 
site, as may be seen by observing how the Sun and Earth 
are related to the Zodiac when motion is given to the 
Arm A, Presuming that the Earth has now arrived at an 
Equinox and that an observation of the Sun is taken from 
her, he would seem to be at the opposite Equinox; like- 
wise if the Earth was at a Solstice and an observation of 
the Sun taken from her, he would seem to be at the oppo- 
site Solstice, which illustrates the fact that the Sun and 
Earth always appear to be in opposite Signs. 

ILLUSTRATION XXVI. 

To Illustrate the inequality of Siderial 
and Solar days. 

The length of the Siderial day is the time that it re- 
quires the Earth to rotate once on her axis, and the length 



ILLUSTRATIONS, 

of the Solar day is the time that elapses between two corn 
secutive transits of the Sun over any given Meridian. 
To illustrate this statement bring the Arm A to the First 
point of the Sign Capricornus (marked Solstice,) and 
bring any Meridian of the Globe to face the Snn directly. 
Then give the Arm motion in the order of the Signs till 
the Earth rotates once on its axis, which rotation repre- 
sents a Siderial day. To complete the Solar day it is 
necessary to revolve the Earth a little further in the same 
direction till the same Meridian is brought to face the 
Sun directly again; consequently the Solar day is 1.365 
longer than the Siderial day, which is caused by the annu- 
al motion in connection with the daily motion of the 
Earth; hence 366 rotations of the Earth on its axis are 
necessary to make 365 Solar days. 

ILLUSTRATION XXVII. 
To Illustrate the Spring and Neap Tides. 

The Spring or High Tides result mainly from the attrac- 
tion of the Sun and Moon when they are on the same 
side of the Earth or on opposite sides; and the Neap 
or Low Tides result mainly from the attraction of the Sun 
and Moon when acting at Right Angles upon the waters 
of the ocean. To illustrate the Spring Tides, move the 
Arm A till the Moon is between the Earth and the Sun, 
and by referring to the Figure on the Base B you will ob- 
serve where the waters are elevated most. To illustrate 



ILLUSTRATIONS. 

the Neap Tides continue the motion of the Arm A till 
the Moon is in Quadrature and by referring to the adjoin- 
ing Figure on the Base B, you will see how these differ 
from the Spring Tides and where they are on the Earth 
in relation to the Sun and Moon. 

ILLUSTRATION XXVIII. 

To Illustrate the effect of Solar and Lunar 
Declination on the Tides. 

As the Moon is always near the plane of the Ecliptic, 
and as the Sun declines 23^ North, and South the same 
number of degrees from the Equator while the Earth is 
making one revolution around him, and as the tendency 
of the waters is to rise highest under the bodies that at- 
tract them, it will be apparent by revolving the Earth and 
Moon around the Sun, and observing the Declination of 
the Sun and Moon, that the waters of the ocean are at 
times as much effected by the attraction of the Sun and 
Moon at the Tropics as at the Equator. 

ILLUSTRATION XXIX. 
To Illustrate the cause of the Trade Winds. 

Wind is air in motion, and the Trade Winds are winds 
at and in the vicinity of the Equator, which seem to be 
constantly blowing Westward. To illustrate their ap- 
parent westward motion, revolve the Arm A in the order 
of the Signs, and observe that any point on the Equator 
of the Globe as it turns on its axis passes through more 



ILLUSTRATIONS. 

space in a given time, than any point in the direction of 
either Pole. This being the case when certain Parallels 
North and South of the Equator are reached, the at- 
mosphere on the Earth keeps pace with the Earth's sur- 
face as she rotates on her axis; jut in the vicinity of the 
Equator it does not move Eastward so fast; hence its con- 
stant apparent Westward motion. 

ILLUSTRATION XXX. 

To Illustrate the influence of the Sun in 
producing the Monsoons. 

One of the principal causes of the Monsoons or period- 
ic winds which blow from the Southwest for about half 
of the year, and from the Northeast for the other half, is 
the Declination of the Sun North and South. 

To illustrate, give motion to the Arm A and revolve the 
Globe once around the Sun, observing in its passage that 
the Sun's rays become alternately vertical on the Northern 
and Southern Hemispheres as far as the Tropics. As he 
declines North of the Equator, regions under him are 
heated by his direct rays and the atmosphere being rar; 
fled, ascends and currents of colder air blow in to take its 
place, and as he declines South of the Equator similar re - 
suits occur, which change the direction of the currents. 
ILLUSTRATION XXXI. 

To Illustrate the cause of Land and Sea Breezes. 

Land and Sea Breezes occur daily in consequence of 
the heat of the Sun and daily motion of the Earth on its 



ILLUSTRATIONS. 

axis. Islands, especially within the Tropics, are exposed 
during the day to the more direct rays of the Sun, as may 
be seen by rotating the Globe on its axis. They grow 
warm sooner each day than the waters which surround 
them, and as they grow warm the heated atmosphere as- 
cends and the winds blow towards the Island to take its 
place. During the night the Islands cool quicker than the 
waters that surround them and the winds blow from them 
towards the the ocean. 

ILLUSTRATION XXXII. 

To Illustrate the Moon as always having the 
same side towards the Earth. 

Set the Moon with the light side next to the Earth. 
Then give motion to the Apparatus and follow the Moon 
with the eye while she is making one revolution around 
the Earth, and it will be apparent that the same side will 
continue towards her; thus making but one rotation on her 
axis while she is making one revolution around the Earth. 

ILLUSTRATION XXXIII. 

To Illustrate the length of Lunar Days and Nights* 

Give motion to the Apparatus till the Moon is between 
the Earth and Sun, and turn the light side of the Moon 
towards the Sun; then continue the motion of the Appar- 
atus till the Moon has passed half round the Earth when 
she will be on the opposite side of the Earth from the 



ILLUSTRATIONS. 

Sun, and the light side of the Moon will be turned away 
from the Sun, showing that each of her Hemispheres has 
but one day and one night during one Lunation, which is 
equal to about twenty-nine and one-half days. 

ILLUSTRATION XXXIV. 

V> Illustrate the Conjunction, Quadrature, 
Ojyposltion and Phases of the Moon. 

Give motion to the Apparatus till the Moon is between 
the Sun and Earth, observing to turn the light side of the 
Moon towards the Sun, and she will be in conjunction and 
at her change] then advance the Earth in her orbit till the 
Moon has made a quarter of a revolution around the 
Earth, observing to turn the light side of the Moon to- 
wards the Sun, and she will be in Quadrature and half-full. 

Continue the motion of the Earth in her orbit till she 

is between the Moon and the Sun, observing to turn the 

light side of the Moon towards the Sun, and it will also 

be towards the Earth, and the Moon will then be in 

opjiosition and full. Again advance the Earth in her orbit 

till the Moo« makes another quarter of a revolution 

around the Earth, observing to turn the light side of the 

Moon towards the Sun, and she will be entering upon her 

fourth quarter and again half-full; hence you will observe 

that when she reaches the end of this quarter she will be 

again at her change. 

Note. — If the Earth and Moon were at their relative distances in 
the Apparatus, the Moon would not appear IN A dirkct line with the 
Earth and Sun, except when she would be at or near one of her 

Nodes. 



ILLUSTRATIONS. 

ILLUSTRATION XXXV. 

To Illustrate the Eccentricity of the Moons Orbit. 

Give motion to the Apparatus and the Moon may be 
seen moving around the Earth, and alternately approach- 
ing and receding from the Earth, while passing around it* 

ILLUSTRATION XXXVI. 

To Illustrate the relation of the Plane of the 
Moons Orbit to the Plane of the Ecliptic. 

The plane of the Moons Orbit is at an Angle of about 
5 degrees with the plane of the Ecliptic, crossing the 
plane of the Ecliptic at two opposite points called Nodes. 
To illustrate this relation, give motion to the Apparatus 
and the Moon may be seen rising and falling alternately 
above and below the plane of the Ecliptic, which plane 
is represented by the Semi-circle F attached to the Equa- 
tor of the Sun. 

ILLUSTRATION XXXVII. 

To Illustrate the Siderial and Sy nodical 
revolutions of the Moon. 

See Definition 80. 
Give motion to the Apparatus till the Sun, Earth and 
Moon are in conjunction, with the Moon between the Sun 
and Earth. Then move the Arm A in the order of the 
Signs till the Moon has passed exactly once around the 
Earth and she will have made a Siderial revolution ; and 
by advancing the Arm A in the same direction till the 



ILLUSTRATIONS. 

Sun, Moon and Earth are again in conjunction, the 
Moon will have made a Synodical revolution. 

Note. — In consequence of the Annual motion of the Earth, the 
Siderial revolution cf the Moon is about TWO days less than her Syn- 
odical revolution, the length of the former being about 27^ days and 
that of the latter about 29^ days. 

ILLUSTRATION XXXVIII. 

To Illustrate Solar and Lunar Eclipses. 

When the Moon passes between us and the Sun, she 
cuts off some or all of his light, hence a Solar Eclipse; 
and when the Earth comes between the Sun and Moon, 
some or all of her light is cut off, hence a Lunar Eclipse, 
To illustrate Solar and Lunar Eclipses with the Apparatus* 
give it motion and observe the course of the Moon as she 
passes between the Sun and Earth eclipsing the Sun, and 
also as the Earth intervenes between the Sun and Moon 
eclipsing the Moon. 

Note. — From observing the course of the Moon around the Earth 
in the Apparatus, it might be inferred that there is a Solar and a Lunar 
Eclipse every revolution of the Moon around the Earth, but if we con- 
sider the Earth and Moon to assume their proper relative distances from 
the Sun and each other, and that the orbit of the Moon crosses the 
plane of the orbit of the Earth, at an angle of about 5 degrees and 
that the crossing points are slowly changing their places around the 
Earth, it becomes apparent that the Moon will be generally so far 
North or so far South of the plane of the Ecliptic, that her shadow 
will not obscure the light of the Sun, neither the' Earth's shadow ob- 
scure her light. Eclipses of the Sun and Moon can only occur when 
the Moon is at or near a Node and is in a line with the Sun and Earth. 



DEFINITIONS AND EXPLANATIONS. 



The Earth on which we dwell is the third primary- 
planet of the eight that revolve around the Sun. Her 
mean distance from the Sun is about 91,430,000 miles and 
she revolves once around him in about 365^ days, and 
rotates once on her axis in about 24 hours. The distance 
through her center from North to South, which is her Po- 
lar diameter, is about 7,899 miles, and the mean distance 
from any point of her Equator to the opposite point, 
which is her Equatorial diameter, is about 7,926 miles. 
In consequence of the difference of about 26J miles in 
the lengths of these diameters, she is not a sphere, but an 
Oblate Spheroid, which means a sphere flattened on the 
opposite sides. * 

i # A Sphere is a solid or volume bounded by a sur- 
face, every point of which is equally distant from a point 
within, called the center. 

2, The Radius of a Sphere is a straight line drawn 
from the center to any point in the surface. 

3. The Diameter of a Sphere is a straight line 

drawn through its center and each end terminating in its 

surface. 

* Note. — The earth's equatorial circumference is an ellipse whose 
major axis is 1 % miles longer than its minor axis. 



DEFINITIONS. 

4. The axis of the earth is the diameter on which 
it turns once in about 24 hours, and the same imaginary 
line continued North and South until it meets the starry 
heavens constitutes the axis of the Celestial Sphere, 

5. The poles of the earth are the extremities of 
the Earth's axis, and the poles of the heavens are the 
extremities of the Celestial axis. 

6. A circle is a plane surface bounded by a curved 
line, every point of which is equally distant from a point 
within, called the center. ^ 

7. The circumference of a circle is the line that 
bounds the circle. 

8. The radius of a circle is any straight line drawn 
from its center to its circumference. 

9. The diameter of a circle is any straight line 
passing through its center and each end terminating in its 
circumference. 

10. An arc is any part of a circumference. 

1 [ . A plane is a surface such that if any two points be 
taken in it, a straight line joining these points will be 
wholly in the surface. 

12. A curved surface is a surface which is neither 

a plane nor composed of planes. 

* Note. — The word circle, is used instead of circumference in de 
scribing lines on the surface of the globe. 

Note. — The phrase, plane of the circle, is used to denote the 
circle proper. 



DEFINITIONS, 

13. A straight line is one that does not change its 
direction at any point. 

14. A curved line is one that changes its direction at 
every point. 

15. A Point is that which has position, but not mag- 
nitude. 

16. Parallel lines are such as have the same di- 
rection, and are therefore equally distant from each 
other at all corresponding points. 

17. An angle is the opening or difference in direc- 
tion between two lines which meet in a common point 
called the vertex. 

18. A right angle is one that is equal to 90 degrees 
and is the angle which may be formed by drawing a ver- 
tical and a horizontal radius in a circle. 

19. An Acute Angle is one that is less than a 
Right angle, 

20. An obtuse angle is one that is greater than a 
Right angle. * 

21. A great circle is one which passes through the 
center of a Sphere and divides it into two equal parts, f 

* Note. — Oblique Angles, embrace the two proceding classes, 
Obtuse and Acute. 

f Note. — For the sake of convenience, both the Earth and the* 
Heavens are conceived to be marked by Points and divided into parts 
by Lines and Circles, whose Planes cut through them in various di- 
rections. 

Note. — Every Circle, great or small is conceived to be divided 
into 360 equal parts called degrees, therefore a degree is not a fixed 
quantity, but only an aliquot part of any Citcle. 



DEFINITIONS. 

22. The equator is a great Circle which cuts the 

Earth at Right angles with its Axis, and divides it into 

the Northern and Southern Hemispheres. 

Note. — The intersection of the plane of the Bquator with the 
>urface of the Earth, constitutes the Terrestrial Equator, and with the 
concave Sphere of the Heavens the Celestial Equator or the Equi- 
noctial. 

23. The ecliptic, is a great Circle in which the 
Earth performs her annual revolution around the Sun, 
and also in which is the apparent path of the Sun. 

Xote. — The Orbit of the Earth, is her pathway in the Ecliptic. 

24. The obliquity of the ecliptic is the inclina- 
tion of the Ecliptic to the Equinoctial of about 232- de- 
grees. 

25. The equinoctial points are the intersections of 
the Ecliptic and Equinoctial, ^ 

Xote. — In consequence mainly of the Solar and Lunar attraction 
upon the excess of matter around the Equator of the Earth, it is slight- 
ly disturbed in its yearly motion, causing the intersections of the Eclip- 
tic with the Equinoctial to move westward about 50" annually. 

26. Meridians are great Circles, which pass through 

the North and South points, and cross the Equator at 

Right angles. 

Note. — The First or Prime Meridian, is the Meridian from 
which Longitude is reckoned East or West. Longitude is sometimes 
reckoned from the Meridians of Ferro, Paris, Madrid and Washington, 
but usually from the Meridian of Greenwich, England. 

Note. — The word Meridian frequently denotes the upper half of 
-a great Circle, which passes through the North and South points. 

Note. — Meridians are sometimes called Hour Circles, and also 
lines of Longitude, because the Arcs of the Equator intercepted be- 
tween them, are used as measures of Time and Longitude. 



DEFINITIONS. 

27. The Equinoctial Colure is the Meridian which 
passes through the Equinoctial points. 

28. The Solstitial Colure is the Meridian which pass- 
es through the Solstitial points. 

The Solstitial Points are the points where the 

Ecliptic touches the Northern and Southern Tropics. 

Noe. — The East and West points are equidistant from the Poles 
of the Earth, and are where the Sun rises and sets when the Days and 
Nights are equal. 

29. A Small Circle is one that divides a Sphere into 
two unequal parts, as it does not pass through the centre 
of the Sphere. 

30. Parallels of Latitude are small Circles, paral- 
lel to the Equator, and when extented into the Heavens, 
are called Parallels of Declination. 

31. The Tropic of Cancer is the Parallel of Lati- 
tude which touches the Northern point of the Ecliptic 
caMed the Summer Solstice. 

32. The Tropic of Capricorn is the Parallel of Lati- 
tude which touches the Southern point of the Ecliptic 
called the Winter Solstice. 

32. The Arctic or North Polar Circle is the 
Parallel of Latitude which passes through the Pole of the 
Ecliptic, distant about 23^ degrees from the North Pole. 

34. The Antarctic or South Polar Circle is the 
parallel of latitude which passes through the Pole of the 
Ecliptic, distant about 23^ degrees from the South Pole. 



DEFINITIONS. 

35. Torrid Zone, is that portion of the Earth's 
surface which lies between the Tropics, 

36. The North Temperate Zone is that portion of 
the Earth's surface which lies between the Tropic of 
Cancer and the Arctic Circle. 

37. The South Temperate Zone is that portion of 
the Earth's surface which lies between the Tropic of Cap- 
ricorn and the Antarctic Circle. 

38. The North Frigid Zone is that portion of the 
Earth's surface which lies North of the Arctic Circle. 

39. The South Frigid Zone is that portion of the 
Earth' surface which lies South of the Antarctic Circle. 

40. The Sensible Horizon is a Circle touching the 
Earth at the spectators feet and extending to the Heavens. 

41. The Visible Horizon is the line where the Sky 
and Earth seem to meet, forming a Circle around the 
spectator. 

42. The Rational Horizon is a Great circle which 

is parallel to the Sensible Horizon and distant from it 

nearly 4.000 miles, the semi-diameter of the Earth, and 

divides the Earth into upper and lower Hemispheres and 

separates the visible Heavens from the invisible. 

Note. — In consequence of the vast distance to the Starry Sphere^ 
these Horizons seem to coincide in it, so that we see the same Hem- 
isphere of stars that we would see if the upper half of the Earth were 
removed and we were standing on the Rational Horizon. 

Note. — Every place on the Earth has its own Horizon. 



DEFINITIONS. 

43. Refraction of Light is the deflection of the rays 
from their original course, by the medium through which 
they pass. 

44. The Cardinal Points when referred to the Earth 
are North, South, East and West, when referred to the 
Heavens are the Zenith and Nadir, and when referred to 
Ecliptic, they are the Equinoxes and Solstices. 

45. The Mariners Compass is composed of a Mag- 
netic Needle, free to move on a sharp-pointed support 
erected in the centre of a Dial which is divided into 
thirty two equal parts representing the Cardinal and In- 
termediate points of the Horizon. 

46. The Latitude of a place on the Earth is its 
distance measured on its Meridian North or South from 
the Equator. 

47. The Polar distance of a place on the Earth 

is its distance measured on its Meridian from the nearest 

Pole. 

Note. — Latitude and Polar distance are mutually comple- 
ments of each other, as each is measured on the same Meridian, in op- 
posite directions, just 90 degrees. 

48. Longitude is distance measured on the Equator 
or a Parallel from some Standard Meridian, called the 
First or Prime Meridian, East cr West, from o to 180 de- 
grees. 



DEFINITIONS. 

49. Right Ascension is distance Eastward from the 
First Point of the Sign Aries, measured on the Equi- 
noctial from o to 360 degrees. 

Note. — The Declination of a heavenly body, is its distance North 
or South from the Equinoctial. 

Note. — Declination corresponds to Terrestrial Latitude. 

Note. — The Polar distance of a Star, is the complement of its 
Declination. 

50. The Zodiac is that part of the Celestial Sphere 
which lies about 8 degrees on each side of the Ecliptic. 

51. A Right Sphere is one whose Axis lies wholly in 
the Plane of the Horizon, hence the Equator, Parallels 
and Circles of daily motion, are perpendicular to the 
Horizon. 

52. A Parallel Sphere is one whose Axis is perpen- 
dicular to the Plane of the Horizon, hence the Equator 
coincides with the Horizan, and the Parallels and Circles 
of a daily motion, are Parallel witri the Horizon. 

53. An Oblique Sphere is one whose Axis is oblique 

to the Horizon, hence the Equator, Parallels and Circles 

of daily motion, are oblique to the Horizon. 

Note. — The definitions of the different Points, Lines and Circles 
which are used in Astronomy, and the propositions based upon them, 
compose the Doctrine of the Sphere. 

54. The Poles qf thr Horizon are the Zenith and 
Nadir. 

55. The Zenith is that point fti the Celestial Sphere, 
directly over the observers head. 

56. The Nadir is that point in the Celestial Sphere, 
cfTrectly under our feet. 



DEFINITIONS. 

57. A vertical circle rs one that passes through the 
Zenith and Nadir and is perpendicular to the plane of 
the Horizon. 

58. The altitude of a heavenly body is its eleva- 
tion above the Horizon, measured on a vertical circle. 

59. The zenith distance of a heavenly body is the 
complement of its altitude, that is the difference between 
the altitude and 90 degrees, 

60. The azimuth of a heavenly body is the angular 

distance between the plane of the Meridian and that of a 

vertical circle passing through the body, and both passing 

through the Zenith. 

Note. — Azimuth is reckoned on the Horizon East or West from the 
North and South points, from o to 90 degrees. 

61. The amplitude of a heavenly body is the angular 
distance from the Prime Vertical to a vertical circle pass- 
ing through the body. 

Note. — Amplitude is reckoned on the Horizon North or South from 
the Prime Vertical, from o to 90 degrees. 

Note. — Azimuth and Amplitude are mutually complements of each 
other, as each is measured on the same great circle in opposite directions 
just 90 degrees. 

62. Celestial longitude is angular distance East 
from the fir9t point of the Sign Aries, measured on the 
Ecliptic from o to 360 degrees. 

63. Celestial Latitude- is angular distance meas- 
ured on a Secondary from the Ecliptic, from o to 90 
degrees. 



DEFINITIONS. 

64. — The axis of a GREax circle is a straight line pass- 
ing through its center at Right Angles to its Plane. 

65. The pole of a great circle is the Point where its 
Axis cuts through the surface of the Sphere. 

66. Every great circle has two Poles, each of which 
is 90 degrees from the Great Circle. 

Note.— A great circle which passes through the Pole of another 
Great Circle, cuts the latter at Right Angles and is called a Secondary 
to that Circle. 

Note. — Meridians are Secondaries to the Equator. 

67. Perihelion is that point in the Earth's Orbit 
nearest the Sun. 

6&. Aphelion is that point in the Earth's Orbit farth- 
est from the Sun. 

69. The line of the apsides is the line joining the 
Perihelion and Aphelion points. 

70. Angular distance is the difference in direction 
between two points as seen from a third point. 

7 1 . Angular motion is the motion of a point or body 
around another point which is at rest. 

72. Angular velocity is the rate of angular motion. 

Note. — We ascertain the position of a given place on the Globe or 
in the Heavens, by taking its angular distance from two Great Circles, 
the Horizon and the Meridian, or the Horizon and the Prime Vertical, 
they being Coordinate Circles are used for such measurements. 

73. The autumnal equinox is the time when the Sun 
crosses the Equator in going Southward, which occurs 
about the 2 2d of September. 



DEFINITIONS. 

74. The vernal equinox is the time when the Sun 
crosses the Equator in returning Northward, which occurs 
about the 21st of March. 

75. The solstitial points are the two points of the 
Ecliptic most distant from the Equinoctial. 

76. The summer solstice is the time when the Sun 
is at his greatest distance North of the Equinoctial, which 
occurs about the 21st of June. 

77. The winter solstice is the time when the Sun is 
at his greatest distance South of the Equinoctial, whick 
occurs about the 2 2d of December. 

78. The circle of perpetual apparition is the 
boundary of that space in the Heavens around the eleva- 
ted Pole in which the Stars never set. 

79. The circle of perpetual occultation is the 
boundary of that space in the Heavens around the de- 
pressed Pole in which the Stars never rise. 

signs and constellations of the zodiac. 

80. The Ecliptic is divided into 12 equal arcs of 30 
degrees each, called Signs, and beginning at the Vernal 
Equinox they succeed each other Eastward in the follow, 
order: Aries, Taurus, Gemini, Cancer, Leo, Virgo, Libra, 
Scorpio, Sagittarius, Capricornus, Aquarius, Pisces. 

These 12 arcs of the Ecliptic are supposed to have 
corresponded about 2,200 years ago, with 12 constel- 
lations having the same names. But in consequence of 



nn i\f rioNS, 

the retrograde motion of the Equinox Points, t lie 
Signs of the Ecliptic have left the constellations with 
which they were formerly associated. As their motion 
corresponds with that of the Equinoctial Points, they 
have moved Westward about one whole Sign in the period 
referred to, so that the division of the Ecliptic called 
Aries lies in the constellation Pisces and the Sign Taurus 
in the constellation Aries and the Sign Gemini in the con- 
stellation Taurus, &c. Hence at the present time the 
names of the constellations of the Zodiac, North of the 
Equinoctial, commencing at the Vernal Equinox, are 
Pisces, Aries, Taurus, Gemini, Cancer, Leo and continu- 
ing in the same order, those South of the same Great 
Circle, are Virgo, Libra, Scorpio, Sagittarius, Capd- 
cornus and Aquarius. — See Chart on the Base of the Lu- 
natellus Globe. 



STAR GLOBE, 

Letters representing the principal parts of the Stdr Globe. 
T. The Tripod. I. The Hour Index. S. The Spiral Springs. 
M. The Meridian. P. The Polar Bearings. 

B. The Meridian Bearing. Q. The Quadrant. 

H. The Horizon. G. The Globe. 

Directions for putting the parts together. 
1st. Insert the shaft of the Meridian Bearing B, in the 
socket of the shaft of the Tripod T, and turn the screw in the 
Tripod till it comes in contact with the shaft of the Meridian 
Bearing B. 

2nd. Drop one of the two Spiral wire-springs S, into each 
end of the tubular axis of the Globe and put the Hour Index 
marked South on the South Pole, and the one marked North 
on the North Pole, and follow the Spiral wire-springs into the 
ends of the tubular axis of the Globe, with the shafts of the 
Polar Bearings P. 

3rd. Place the groove in the outer end of one of these Bear- 
ings, on the inside of the Meridian M, and remove the small 
plate on the end of the other Polar Bearing, with a small screw 
driver, (taking care not to lose the very small rollers through 
which the screws pass.) and press the IV; 1 ar Baring towards 
the center of the Globe till it takes its place on the inside of 
the Meiidian M, and then replace the small plate which was re- 
moved from the Polar Bearing, and the Globe is ready for use. 




STAB GLOBE. 



STAR GLOBE. 

(Diameter 12 inches.) 

The Star Globe, being complete in all its appointments, con- 
tains elements of utility and durability which are not 
found in any other. Unlike many others, that are now being 
made without a Graduated Meridian, or Hour Indices, or 
Quadrant of Altitude, or Horizon, it possesses all of these 
parts, and all others which are essential either for convenience 
or instruction. 

GLOBE STAND. 

The Globe is mounted on a metallic Tripod, which is light, 
substantial, convenient, neatly japanned, and tastefully 
ornamented. 

MERIDIAN. 

The Meridian which contains the Globe is brass, plated 
with nickel, and graduated on both sides. One-fourth 
of its circumference is inserted in a concave metallic bearing 
to give it permanence, which bearing is united with the central 
shaft of the Tripod by a swivel, so that it will revolve hori- 
zontally, without changing tli l 1 position of the Tripod. 

HORIZON. 

The Horizon is also composed of metal, and it is so fitted to 
the Meridian at its horizontal diameter, that it may be 

CONVENIENTLY REMOVED AND REPLACED. Upon it is a 

Map containing the Signs of the Ecliptic and their divisions 



STAB GLOBE. 

into degrees, the Months of the Fear and their divisions into 
Hays, the Cardinal and Minor Points of the Compass and the 
degrees of Azimuth and Amplitude. 

THE GLOBE. 

The Globe itself which is twelve inches in diameter, is con- 
structed of materials that are tough, light, durable and not 
perceptibly effected by any climatic changes of temperature. 
It is skillfully made, which in conjunction with the strength of 
the materials of which it is composed, renders its surface proof 
against change of form unless improperly used. 

GLOBE MAP. 

The Geographical Map with which this Globe is covered is 
issued by the Map Publishing House of W. & A. K. John- 
ston, Edinburgh, Scotland, and this is a sufficient guarantee 
that it has no superior. It is engraved in copper and printed 
in colors, and contains the Ocean Currents, the Isochimal and 
Isothermal lines, the latest Political Divisions and Boundaries 
of all Countries, the corrected Boundaries of the States and 
Territories of the United States, the Topography of various 
places and Countries as reported by modern Explorers, 
together with much new matter which is the outgrowth of 
both National and International enterprise. This array of 
additional knowledge, combined with that which the Map 
originally contained, gives to the Globe which it covers a value 
which many others do not possess. 



STAR GLOBE. 

GLOBE MOVEMENT. 

The Axis of the Globe, unlike all others, is made of metal 
tubing, and in its ends are placed springs and bearings on 
which it revolves. The outer ends of these bearings are 
grooved so as to receive the inner edge of the Meridian, and 
they move on it when a change in the position of the axis of 
the Globe is desired, a novel and very convenient device for 
this purpose. 

HOUR INDICES. 

The Hour Indices, which are placed around the Poles of 
the Globe are stamped out of sheet brass and nickel-plated. 
Each Index is divided into twenty-four equal parts, and these 
parts have associated with them characters that represent the 
hours of the day. 

QUADRANT OF ALTITUDE. 

The Quadrant of Altitude is a flexible strip of metal grad- 
uated into equal parts, each corresponding in length to a de- 
gree on the Globe, and bent when in use so as to closely fit its 
surface. 

THE ANALEMMA. 

The Analemma on the Globe is a diagram which extends 
across tr^e Torrid Zone. It contains the days of each month 
in the year, so arranged, that if the month and day of the 
month are given, the Declination of the Sun at that time may 
be readily found, or if the Declination of the Sun is given, 
the month and day of the month may be readily found, and 



the Sign and the degree of the Ecliptic in which he is, also, 
the Equation of time, or the difference between Sun and Clock 
time for any day of the year. 

THE STAR GLOBE is manufactured by Skillful 
Mechanics in the most substantial manner, and an 
EXACT duplicate of any part of it can be obtained at any 
time by applying to the Patentee. 

A Manual containing a comprehensive series of Problems, 
Examples and Illustrations will accompany each Globe. 



